As noted in the press release announcing his retirement, Justice Kennedy was appointed by President Ronald Reagan, a Republican, and took the oath of office in February 1988. Although he was nominated by a Republican, which typically indicates a more conservative leaning in court decisions, Kennedy has, since 1988, been something of a mixed bag. This is especially true when it comes to the court's decision on abortion-related cases.

In fact, although he leans conservative, Kennedy has largely been viewed as a sort of swing vote in the court, particularly for more social-based issues (see: same-sex marriage) and abortion. This made him a vital vote in the court, which currently has four staunchly conservative judges (Chief Justice John Roberts and Justices Clarence Thomas, Samuel Alito, and Neil Gorsuch, who was appointed by President Trump) and four staunchly liberal judges (Justices Ruth Bader Ginsburg, Sonia Sotomayor, Elena Kagan, and Stephen Breyer).

This is why abortion-rights advocates are so unsettled by Kennedy's retirement; he has been a necessary factor to swing the court in several landmark abortion cases over the past 30 years. Without him there, should Trump nominate an anti-abortion justice — as he has indicated that he would — abortion rights could fall quickly.

"In 1992’s Planned Parenthood v. Casey, instead of voting to overturn Roe v. Wade as some feared, Kennedy helped cement a woman’s right to make her own decisions about continuing or ending a pregnancy," Nancy Northup, President and CEO of the Center for Reproductive Rights, said in a statement on Wednesday obtained by Elite Daily. "Casey stood for liberty and equality, holding that ‘[t]he ability of women to participate equally in the economic and social life of the Nation has been facilitated by their ability to control their reproductive lives.’"

In that case, Kennedy agreed with the majority to rule that lawmakers cannot place an "undue burden" on women seeking abortions. This was a landmark case that set an important precedent to protect women's right to abortion — holding, through force of law, that abortion should not only be theoretically legal, but also realistically accessible.

That "undue burden" standard came up again in 2016, during another landmark abortion case: Whole Woman's Health v. Hellerstedt. In that case, Kennedy joined the liberal justices to decide in the majority that a Texas law that restricted abortion access was unconstitutional. Again, this was a 5-4 case. This set a major legal precedent, giving anti-abortion lawmakers fewer options to restrict access.

"Two years ago today, he joined the majority in Whole Woman’s Health v. Hellerstedt, the most important abortion rights case in a generation, which struck down a Texas law that would have closed 75 percent of the state’s abortion clinics," Northup further said in the Center for Reproductive Rights' statement (the center filed the lawsuit in that case).

On the flip side, abortion law watchers have already seen what happens when Kennedy does not side with the liberal judges. This happened, for instance, in 2007, in Gonzales v. Carhart. In that case, Kennedy wrote the opinion for the majority, and he was joined by the conservative judges in a 5-4 ruling. There, the majority ruled that the so-called Partial-Birth Abortion Ban Act, which banned a specific late-term abortion procedure, was not unconstitutional and did not infringe on women's rights to abortion access. (I'll note here that in 2014 — the most recent year with data — 1.3 percent of all abortions in the United States happened after 21 weeks of pregnancy, and most abortions that happen after 20 weeks are because of fetal anomalies, health risks, and other devastating reasons.)

Followers of abortion cases also saw what happens without Kennedy's support for abortion rights just this week, in NIFLA v. Becerra. In that case, Kennedy sided with the conservatives — once again, in a 5-4 majority — to rule that a law requiring crisis pregnancy centers to post information stating that they are not medically licensed and about where low-cost or free reproductive care services are offered "likely violates" the First Amendment.

Without Kennedy to swing the vote, the liberal justices on the court do not have the majority, plain and simple. Trump has indicated repeatedly that he would appoint somebody who would work to overturn Roe v. Wade, the 1973 case that ruled abortion a constitutional right. Should he do so — and should the Senate, which is currently majority Republican and planning to vote on the nomination before the effects of the midterm elections will be felt, approve his nomination — there will be an unflinching majority when it comes to abortion cases, and they will not be ruling against restrictive laws.

"Because President Trump will nominate the next Supreme Court Justice, a woman’s constitutional right to access legal abortion is in dire, immediate danger," NARAL Pro-Choice America President Ilyse Hogue said in a statement obtained by Elite Daily.

Now, when it comes to actually getting rid of abortion rights in America, it's not as simple as justices saying they're going to overturn Roe v. Wade and then overturning it. It's more like, to start, chipping away at it using certain laws and legal challenges (i.e. ruling that bans on certain types of procedures, like the Partial-Birth Abortion Ban Act, are legal).

Abortion rights advocates, I've been told, are expecting a case about a ban on certain methods of the abortion procedure to end up in the Supreme Court soon (there are currently several cases about that, particularly banning dilation and evacuation procedures, that could make it to the highest court). That could be the next battle for abortion rights in the Supreme Court, and if the nomination of Gorsuch — and his rulings thus far — is any indication, that battle does not seem likely to go in abortion rights advocates' way without Kennedy there.

The other thing is, a case like that doesn't need to come up next term or even within Trump's presidency; a Supreme Court nomination is a lifelong one without limits, so it could happen next year or in five years, and Trump's two nominees will still have the opportunity to push the majority of the court against abortion rights.